Techniques have been developed for the measurement of foot orientation and position during the swing phase of gait using a tri-axial accelerometer and gyroscope inertial monitoring units (IMU) placed on the foot, however such work has been concerned primarily with foot movement in the medial-lateral and cranial-caudal direction during the swing phase and not with distance or the direction travelled. Other techniques for measuring stride length using a tri-axial gyroscope, accelerometer and magnetometer sensor configuration with one placed on the leg and another placed on the thigh to measure stride length, however such a technique requires the length of both the upper leg and lower leg to be known.
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